using System;
using System.IO;
using Drill.Configuration;
using Drill.Core.Utilities;

namespace Drill.TestSupport
{
    public class TestConfigFileLoader
    {
        private const string UnityProviderTestConfigFilename = @"UnityProvider\AppConfig.config";
		private const string DefaultTestConfigFilename = @"TestConfigFiles\Minimal.config";
		private const string DependencyResolverName = "Default";

        private readonly string _testConfigFilename;

        private TestConfigFileLoader(string testConfigFilename)
        {
            ArgumentException argumentException =
                ValidationUtility.GetArgumentExceptionForStringIsNullOrIsEmptyOrContainsOnlyWhitespace(testConfigFilename, "testConfigFilename");
            if (null != argumentException)
            {
                throw argumentException;
            }

            if (Path.IsPathRooted(testConfigFilename))
            {
                _testConfigFilename = testConfigFilename;
            }
            else
            {
                string testDataDirectory = TestDataDirectoryLocator.FindTestDataDirectory();
                _testConfigFilename = Path.Combine(testDataDirectory, testConfigFilename);
            }
        }

        private IDependencyResolverConfiguration LoadTestConfig()
        {
			return ConfigurationLoader.LoadDependencyResolverConfig(DependencyResolverName, _testConfigFilename);
        }

        public static string GetDefaultTestConfigurationFilename()
        {
            return new TestConfigFileLoader(DefaultTestConfigFilename)._testConfigFilename;
        }

        public static string GetUnityProviderTestConfigurationFilename()
        {
            return new TestConfigFileLoader(UnityProviderTestConfigFilename)._testConfigFilename;
        }

        public static IDependencyResolverConfiguration LoadDefaultTestConfig()
        {
            return new TestConfigFileLoader(DefaultTestConfigFilename).LoadTestConfig();
        }

        public static IDependencyResolverConfiguration LoadUnityProviderTestConfig()
        {
            return new TestConfigFileLoader(UnityProviderTestConfigFilename).LoadTestConfig();
        }
    }
}